Interesting case Neuro 27

Salient findings:

1. Defect in the olfactory groove in the floor of the left cribriform plate
   
   
2. CSF-density structure filling the superior left ethmoid air cell arising from this bony dehiscence.
   Features in keeping with meningocele.
   
   
3. No definitive features of meningoencephalocele - this would be better appreciated on MRI if available.
   
   
4. On the CT of the brain, expanded sella turcica with empty sella appearances. Sign of idiopathic intracranial hypertension (IIH). No absolute dilation of the optic nerve sheaths or tortuosity seen.
   
   

Principle Diagnosis:

Cribriform plate dehiscence and meningocele

Other key findings:

Features consistent with IIH. The presence of IIH is likely a key exacerbating factor in compounding the initial insult of a potentially iatrogenic bony defect following ENT procedures.

Learning points:

1. Causes of cribriform plate defects/dehiscence. Note that in this case, the patient has 2 underlying potentially aetiological factors (*) contributing to the outcome.
   
   a. Trauma with anterior skull base fracture
   
   b. Idiopathic Intracranial Hypertension (IIH) 
   
   c. Iatrogenic surgical causes:
   - ENT procedures such as endoscopic sinus surgery and septoplasty * etc.
   - Pituitary or skull base neurosurgical procedures
   
   d. Congenital
   
   
2. MRI useful to assess for associated encephalocele accompanying the meningocele and if so, to define its contents in terms of volume and anatomy of the cerebral parenchyma involved.
   
   
3. Sx/complications: CSF-leak, meningitis, cerebral abscess, focal neurological deficits for large meningoencephaloceles